import java.util.Scanner;
import java.util.Calendar;
 
public class Main {
    public static void main(String[] args) throws Exception {
        Calendar cl = Calendar.getInstance();
      
        int y = 2015;
        int m = 1;
        cl.set(y,m-1,1);
        int d = cl.getActualMaximum(Calendar.DAY_OF_MONTH);
        
        int tens = d / 10; 
        int ones = d % 10;
        int count = 0;
        
        //12回繰り返す
        for(m=1;m<=12;m++){
        	////2015年のカレンダーの日次回数繰り返す
        	for(int x= 1;x<=d;x++){
        		if(m==tens+ones){
        		count +=1;
        		}
        	}
        }
        System.out.println(count);
    }
}